A woman throws an object of mass 500 g with a speed of 25 m/s.

(i) What is the impulse imparted to the object?

(ii) If the object hits a wall and rebounds with half

the original speed, what is the change in momentum of the object?

Mass of the object (m) = 500g = 0.5 kg

Speed of the object (v) = 25 m/s

(i) Impulse imparted to the object = Change in the momentum = mv-mu

= m(v-u)

= 0.5(25-0) = 12.5 N-s

(ii) Velocity of the object after rebounding = -25/2 m/s

v’ = -12.5 m/s

Change in momentum = m(v’ - v)

= 0.5 (-12.5 -25)

= -18.75 N-s